Chronic Traumatic Encephalopathy (CTE)

Medically Reviewed by Jabeen Begum, MD on February 14, 2024
5 min read

CTE stands for chronic traumatic encephalopathy. It's a brain disease caused by repeated head injuries that may include concussions.

It mostly happens in athletes who play contact sports like football and ice hockey. Doctors first identified it under a different name in the 1920s in aging boxers. CTE results from cumulative damage and usually happens years later.

Although there’s no cure, you or your child can take steps to avoid getting CTE.

Even if your “bell has been rung” a few times, it doesn’t mean you’ll get the disease. But you should know what to watch out for.

When you’ve had repeated blows to the head, including concussions, they set off a slow series of events that may lead to brain problems.

Repeated brain injuries can lead to a buildup of tau, a protein that’s found in the brains of people with Alzheimer's.

Tau is not all bad. It stabilizes brain cells. But when it builds up due to an impact to the brain, it tangles and clumps together. This slowly kills cells called neurons. The clumped tau also spreads to other cells and makes it harder for the brain to work. This is CTE.

Since not everyone with a history of brain trauma gets CTE, some researchers think other things, like genetics, may play a role. But head impacts are the only proven cause. And you may get a second head injury before fully healing from an earlier one, called second impact syndrome. Experts think athletes who get a concussion and make an early return to their sport have a higher chance of getting this condition.


You may have:

  • Memory loss
  • Confusion
  • Impulsive or erratic behavior
  • Bad judgment
  • Aggression
  • Depression
  • Paranoia
  • Dementia
  • Trouble planning and organizing
  • Emotional instability
  • Substance misuse
  • Suicidal thoughts or behavior

These conditions usually begin years, sometimes decades, after your last brain injury or when you stopped playing. Experts think CTE symptoms show up in two ways during different periods of your life. The first form appears in your late 20s or early 30s and causes problems with mental health and behavior. You may have depression, anxiety, aggression, and impulse control issues. 

Later, around age 60, is when the second form may crop up, causing trouble with memory and thinking. Some symptoms are similar to those seen in people with Alzheimer's or Parkinson's disease, which makes it hard to diagnose. Let your doctor know about any head injuries you’ve had, no matter how long ago, and when your symptoms started.

Right now, the only way to confirm a CTE diagnosis is to look at samples of brain tissue under a microscope, which can only happen after death. But doctors can make a probable diagnosis based on your symptoms, history of head injuries, and exams. They'll also rule out other conditions with these tests:

  • Computed tomography (CT) scans.
  • Magnetic resonance imaging (MRI) scans.
  • Positron emission tomography (PET) scans.
  • Spinal tap (lumbar puncture)

Researchers are developing tests to diagnose CTE earlier. There have already been breakthroughs in tau imaging, and scientists have learned a lot about the condition. Their work may lead to advances in the diagnosis and treatment of the disease.

When doctors discovered CTE in prizefighters in the 1920s, they called it “dementia pugilistica.” The condition became so well known that for years, fighters with slurred speech and behavior issues were called “punch drunk.”

But in recent years, CTE has been found in other athletes, most notably former football and hockey players. You may have read in the news about NFL players, like Junior Seau, who were diagnosed with the disease after their deaths. Although doctors can suspect CTE, they can’t confirm the diagnosis until they autopsy the brain.

Researchers also have found the condition in athletes who competed through only high school or college, in some cases decades before they died. The average age of people diagnosed with CTE is their early 40s.

Others, including military veterans who’ve had a head injury, are also vulnerable to the disease. But people who play or have played contact sports such as football, ice hockey, and rugby face the highest risk. Those who take part in activities on a road or concrete, like cycling, rollerblading, or skateboarding, also have a higher chance of CTE. 

Kids and their parents should also be alert. Children who play these sports may have higher odds of getting a serious brain injury than even pro athletes. Youth football players take hits to the head nearly equal to that of college players – and a child’s brain is less insulated than an adult’s, leaving the brain cells more sensitive to the shock of concussions. Some soccer leagues have banned "heading" the ball.

While there's no cure for CTE, and it will get worse over time, there are treatments for some symptoms of the disease. They include:

  • Physical therapy for trouble with movement
  • Occupational therapy to help with daily living needs
  • Speech and language therapy to help with memory and speech problems

You can also make lifestyle changes for a healthier life with CTE:

  • Take notes. Writing things down in a notebook, using a calendar, or a voice memo can help if you have memory problems.
  • Create a routine. Structure in your day can make you feel more stable.
  • Be aware of impulsive behaviors. CTE can damage areas of the brain that control impulsive behaviors like gambling, overspending, and alcohol and drug misuse.
  • Use relaxation techniques. Deep breathing, meditation, or simply counting to 10 can help to control your emotions, anxiety, and stress.
  • Find support. Talk to people you can trust, like friends, family, or people in your faith community.
  • Sleep well. A lack of shut-eye and sleep disorders like sleep apnea can worsen CTE symptoms. 
  • Exercise. Physical activity eases stress and pain and enhances your overall quality of life.
  • Eat a balanced diet. It can improve your health and give you more energy.

Kids and higher-level athletes should take some steps to lower their chances of getting a concussion:

  • Wear the right equipment.
  • Make sure all gear is worn properly.
  • Check the playing field, and tell the coach about any uneven areas and holes.
  • Don't use unnecessary aggression during the game.
  • Learn and use the proper technique for your sport.
  • Wear a seatbelt.
  • Don't play while you're hurt.

There’s work for the coach here, too. They should limit the number and length of contact practices. Many states now have laws on the books about that.

Talk to your doctor if you have any symptoms of CTE like trouble thinking, remembering, or concentrating, or mood or behavior changes. If you have suicidal thoughts or think about hurting others, get help right away.